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1.
Brain ; 147(7): 2483-2495, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38701342

RESUMO

Network neuroscience offers a unique framework to understand the organizational principles of the human brain. Despite recent progress, our understanding of how the brain is modulated by focal lesions remains incomplete. Resection of the temporal lobe is the most effective treatment to control seizures in pharmaco-resistant temporal lobe epilepsy (TLE), making this syndrome a powerful model to study lesional effects on network organization in young and middle-aged adults. Here, we assessed the downstream consequences of a focal lesion and its surgical resection on the brain's structural connectome, and explored how this reorganization relates to clinical variables at the individual patient level. We included adults with pharmaco-resistant TLE (n = 37) who underwent anterior temporal lobectomy between two imaging time points, as well as age- and sex-matched healthy controls who underwent comparable imaging (n = 31). Core to our analysis was the projection of high-dimensional structural connectome data-derived from diffusion MRI tractography from each subject-into lower-dimensional gradients. We then compared connectome gradients in patients relative to controls before surgery, tracked surgically-induced connectome reconfiguration from pre- to postoperative time points, and examined associations to patient-specific clinical and imaging phenotypes. Before surgery, individuals with TLE presented with marked connectome changes in bilateral temporo-parietal regions, reflecting an increased segregation of the ipsilateral anterior temporal lobe from the rest of the brain. Surgery-induced connectome reorganization was localized to this temporo-parietal subnetwork, but primarily involved postoperative integration of contralateral regions with the rest of the brain. Using a partial least-squares analysis, we uncovered a latent clinical imaging signature underlying this pre- to postoperative connectome reorganization, showing that patients who displayed postoperative integration in bilateral fronto-occipital cortices also had greater preoperative ipsilateral hippocampal atrophy, lower seizure frequency and secondarily generalized seizures. Our results bridge the effects of focal brain lesions and their surgical resections with large-scale network reorganization and interindividual clinical variability, thus offering new avenues to examine the fundamental malleability of the human brain.


Assuntos
Lobectomia Temporal Anterior , Conectoma , Epilepsia do Lobo Temporal , Lobo Temporal , Humanos , Feminino , Masculino , Adulto , Epilepsia do Lobo Temporal/cirurgia , Epilepsia do Lobo Temporal/fisiopatologia , Epilepsia do Lobo Temporal/diagnóstico por imagem , Epilepsia do Lobo Temporal/patologia , Lobo Temporal/patologia , Lobo Temporal/cirurgia , Lobo Temporal/diagnóstico por imagem , Lobectomia Temporal Anterior/métodos , Pessoa de Meia-Idade , Adulto Jovem , Imagem de Tensor de Difusão , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/patologia , Epilepsia Resistente a Medicamentos/cirurgia , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/fisiopatologia , Epilepsia Resistente a Medicamentos/patologia
2.
Exp Cell Res ; 440(1): 114130, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38885805

RESUMO

Prostate cancer (PCa) is the most prevalent malignant tumor of the genitourinary system, and metastatic disease has a significant impact on the prognosis of PCa patients. As a result, knowing the processes of PCa development can help patients achieve better outcomes. Here, we investigated the expression and function of ORC6 in PCa. Our findings indicated that ORC6 was elevated in advanced PCa tissues. Patients with PCa who exhibited high levels of ORC6 had a poor prognosis. Following that, we investigated the function of ORC6 in PCa progression using a variety of functional experiments both in vivo and in vitro, and discovered that ORC6 knockdown inhibited PCa cell proliferation, growth, and migration. Furthermore, RNA-seq was employed to examine the molecular mechanism of PCa progression. The results revealed that ORC6 might promote the expression of PLK1, a serine/threonine kinase in PCa cells. We also discovered that ORC6 as a novel miR-361-5p substrate using database analysis, and miR-361-5p was found to lower ORC6 expression. Additionally, RNA immunoprecipitation (RIP) and luciferase reporter tests revealed that the transcription factor E2F1 could regulate ORC6 expression in PCa cells. PLK1 overexpression or miR-361-5p inhibitor treatment effectively removed the inhibitory effects caused by ORC6 silencing. Notably, our data showed that therapeutically targeting the miR-361-5p/ORC6/PLK1 axis may be a viable therapy option for PCa.


Assuntos
Proteínas de Ciclo Celular , Movimento Celular , Proliferação de Células , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , MicroRNAs , Quinase 1 Polo-Like , Neoplasias da Próstata , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas , Animais , Humanos , Masculino , Camundongos , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica/genética , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , MicroRNAs/metabolismo , Complexo de Reconhecimento de Origem/genética , Complexo de Reconhecimento de Origem/metabolismo , Prognóstico , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Neoplasias da Próstata/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo
3.
Ann Surg Oncol ; 31(9): 5815-5826, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38954088

RESUMO

BACKGROUND: Because of to the removal of subclassification of papillary renal cell carcinoma (pRCC), the survival prognostification of localized pRCC after surgical treatment became inadequate. Sarcopenia was widely evaluated and proved to be a predictive factor for prognosis in RCC patients. Therefore, we comprehensively investigated the survival prediction of the body composition parameters for localized pRCC. METHODS: Patients pathologically diagnosed with pRCC between February 2012 and February 2022 in our center were enrolled. The body composition parameters, including skeletal muscle index (SMI), subcutaneous adipose tissue (SAT), and perirenal adipose tissue (PRAT), were measured by the images of preoperative computed tomography (CT). The primary outcome was set as progression-free survival (PFS), and the cutoff values of body composition parameters were calculated by using the Youden from receiver operating characteristic curve (ROC) curves. Univariate and multivariate Cox proportional regression analyses were performed to explore independent risk factors for survival prediction. Then, significant factors were used to construct a prognostic nomogram. The performance of the nomogram was evaluated by Harrell's C-index, calibration curves and time-dependent ROC curves. RESULTS: A total of 105 patients were enrolled for analysis. With a median follow-up time of 30.48 months, 25 (23.81%) patients experienced cancer progression. The percentage of sarcopenia was 74.29%. Univariate Cox analysis identified that gender, PRAT, SAT, skeletal muscle (SM), sarcopenia, surgical technique, and tumor diameter were associated with progression. Further multivariate analysis showed that sarcopenia (hazard ratio [HR] 0.15, 95% confidence interval [CI] 0.03-0.66), SAT (HR 6.36, 95% CI 2.39-16.93), PRAT (HR 4.66, 95% CI 1.77-12.27), tumor diameter (HR 0.35, 95% CI 0.14-0.86), and surgical technique (HR 2.85, 95% CI 1.06-7.64) were independent risk factors for cancer progression. Then, a prognostic nomogram based on independent risk factors was constructed and the C-index for progression prediction was 0.831 (95% CI 0.761-0.901), representing a reasonable discrimination, the calibration curves, and the time-dependent ROC curves verified the good performance of the nomogram. CONCLUSIONS: A prognostic nomogram, including sarcopenia, SAT, PRAT, tumor diameter, and surgical technique, was constructed to calculate the probability of progression for localized pRCC patients and needs further external validation for clinical use in the future.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Nomogramas , Sarcopenia , Humanos , Sarcopenia/patologia , Sarcopenia/diagnóstico por imagem , Masculino , Feminino , Estudos Retrospectivos , Neoplasias Renais/patologia , Neoplasias Renais/cirurgia , Neoplasias Renais/mortalidade , Pessoa de Meia-Idade , Carcinoma de Células Renais/cirurgia , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/mortalidade , Taxa de Sobrevida , Seguimentos , Prognóstico , Idoso , Curva ROC , Intervalo Livre de Progressão , Composição Corporal , Adulto
4.
Mol Phylogenet Evol ; 199: 108147, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38986755

RESUMO

Parasitengona (velvet mites, chiggers and water mites) is a highly diverse and globally distributed mite lineage encompassing over 11,000 described species, inhabiting terrestrial, freshwater and marine habitats. Certain species, such as chiggers (Trombiculidae), have a great medical and veterinary importance as they feed on their vertebrate hosts and vector pathogens. Despite extensive previous research, the classification of Parasitengona is still contentious, particularly regarding the boundaries between superfamilies and families, exacerbated by the absence of a comprehensive phylogeny. The ontogeny of most Parasitengona is distinct by the presence of striking metamorphosis, with parasitic larvae being heteromorphic compared to the predatory free-living deutonymphs and adults. The enigmatic superfamily Allotanaupodoidea is an exception, with larvae and active post-larval stages being morphologically similar, suggesting that the absence of metamorphosis may be either an ancestral state or a secondary reversal. Furthermore, there is disagreement in the literature on whether Parasitengona had freshwater or terrestrial origin. Here, we inferred phylogenetic relationships of Parasitengona (89 species, 36 families) and 307 outgroups using five genes (7,838 nt aligned). This phylogeny suggests a terrestrial origin of Parasitengona and a secondary loss of metamorphosis in Allotanaoupodoidea. We recovered the superfamily Trombidioidea (Trombidioidea sensu lato) as a large, well-supported, higher-level clade including 10 sampled families. We propose a new classification for the terrestrial Parasitengona with three new major divisions (epifamilies) of the superfamily Trombidioidea: Trombelloidae (families Audyanidae, Trombellidae, Neotrombidiidae, Johnstonianidae, Chyzeriidae); Trombidioidae (Microtrombidiidae, Neothrombiidae, Achaemenothrombiidae, Trombidiidae, Podothrombiidae); and Trombiculoidae (=Trombiculidae sensu lato). Adding them to previously recognized superfamilies Allotanaupodoidea, Amphotrombioidea, Calyptostomatoidea, Erythraeoidea, Tanaupodoidae and Yurebilloidae.


Assuntos
Metamorfose Biológica , Filogenia , Animais , Metamorfose Biológica/genética , Ecossistema , Evolução Biológica , Larva/crescimento & desenvolvimento , Larva/classificação , Larva/genética , Ácaros/classificação , Ácaros/genética , Ácaros/anatomia & histologia , Ácaros/crescimento & desenvolvimento , Análise de Sequência de DNA
5.
Phys Rev Lett ; 132(8): 086701, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38457714

RESUMO

Since the discovery of antiferromagnetism, metallic oxide RuO_{2} has exhibited numerous intriguing spintronics properties such as the anomalous Hall effect and anisotropic spin splitting effect. However, the microscopic origin of its antiferromagnetism remains unclear. By investigating the spin splitting torque in RuO_{2}/Py, we found that metallic RuO_{2} exhibits a spatially periodic spin structure which interacts with the spin waves in Py through interfacial exchange coupling. The wavelength of such structure is evaluated within 14-20 nm depending on the temperature, which is evidence of an incommensurate spin density wave state in RuO_{2}. Our work not only provides a dynamics approach to characterize the antiferromagnetic ordering in RuO_{2}, but also offers fundamental insights into the spin current generation due to anisotropic spin splitting effect associated with spin density wave.

6.
Chemistry ; 30(43): e202401303, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38794842

RESUMO

Developing pragmatic strategies for accessing functional benzofuran-2-ones from 3-([1,1'-biphenyl]-2-yl)benzofuran remains an enduring challenge. Herein, we have achieved a highly discriminating electrochemical oxidative dearomative spiroannulation of 3-([1,1'-biphenyl]-2-yl)benzofuran, culminating in the synthesis of 2H-spiro[benzofuran-3,9'-fluoren]-2-one derivatives. By harnessing the electrophilic intermediates of benzofuryl radical cations supported by DFT calculations, we attain exceptional regioselectivity while eliminating the need for stoichiometric oxidants. Mechanistic investigations reveal a sequence of events involving the benzofuran radical cation, encompassing the capture of H2O, nucleophilic arene attack, and subsequent deprotonation, ultimately yielding the final benzofuran-2-ones.

7.
J Magn Reson Imaging ; 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38243667

RESUMO

BACKGROUND: Identifying patients at high risk of stroke recurrence is important for stroke prevention and treatment. PURPOSE: To explore the characteristics of T1 hyperintense plaques (HIP) and their relationship with stroke recurrence in patients with symptomatic intracranial atherosclerotic stenosis (sICAS). STUDY TYPE: Retrospective. POPULATION: One hundred fifty-seven patients with moderate-to-severe (≥50%) nonocclusive sICAS and MRI studies (42 females and 115 males, mean age 58.69 ± 10.68 years). FIELD STRENGTH/SEQUENCE: 3D higher-resolution black-blood T1-weighted fast-spin-echo sequence at 3.0 T. ASSESSMENT: HIP (signal intensity [SI] of plaque-to-adjacent gray matter >1.0 on non-contrast T1-weighted images) and non-HIP plaques were identified. HIP plaques were categorized as edge type (high SI adjacent to lumen) and non-edge type (high SI within plaque). Clinical and imaging features of different plaque types were compared. Stroke recurrence was assessed through telephone or medical records at 3 and 6 months, and then once a year post-MRI. The relationship between edge type and non-edge types HIP with stroke recurrence was analyzed. STATISTICAL TESTS: Student's t test, Mann-Whitney U-test, chi square test and Fisher's exact test to compare features between plaque types. Kaplan-Meier curves (with log-rank tests) and Cox proportional hazards regression to assess relationship between stroke recurrence and different plaque types. A two-tailed P-value of <0.05 was considered statistically significant. RESULTS: Of 157 culprit lesions, 87 (55%) were HIPs (43 edge type, 44 non-edge type) and 70 (45%) were non-HIPs. Plaque thickness, area, and volume were significantly higher for HIPs than for non-HIPs. Among patients with HIPs, edge type was significantly more likely in the posterior circulation (53.5% vs. 27.3%), and had significantly higher plaque thickness, length, area, volume, plaque burden, and remodeling index than non-edge type. Edge-type HIP was significantly more common than non-edge HIP in patients with diabetes mellitus (51.2% vs. 29.5%) and dyslipidemia (79.1% vs. 54.5%). During median follow-up of 27 months, 33 patients experienced stroke recurrence. Recurrence was associated with edge-type HIP (adjusted hazard ratio = 2.83; 95% confidence interval: 1.40-5.69), both in the overall cohort (34.9% vs. 15.8%) and in patients with HIP (34.9% vs. 9.0%). Age ≥60 years and edge-type HIP had a significant interaction. DATA CONCLUSIONS: Hyperintense plaque may be categorized as edge type or non-edge type. Edge-type HIP may be a potential MRI biomarker of stroke recurrence. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.

8.
J Org Chem ; 89(15): 10748-10759, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-38996054

RESUMO

Density functional theory (DFT) calculations were conducted to explore the mechanisms and origins of regio- and stereoselectivities underlying the [3 + 3] annulation reaction between α-bromoenals and 5-aminoisoxazoles with N-heterocyclic carbene (NHC) as the catalyst. The reaction occurs in nine steps: (1) nucleophilic addition of NHC to α-bromoenal, (2) Breslow intermediate formation through 1,2-proton transfer, (3) debromination, (4) α,ß-unsaturated acyl azolium intermediate formation via 1,3-proton transfer, (5) addition of α,ß-unsaturated acyl azolium intermediate to 5-aminoisoxazole, (6) deprotonation, (7) protonation, (8) ring closure, and (9) elimination of NHC. For the fifth step, 1,2-addition suggested in the experiment was not supported by our results. Instead, we found that Michael addition is energetically the most feasible pathway and the stereo-controlling step that preferentially provides the S-configuration product. DFT-computed results and experimental findings agree well. Analysis of distortion/interaction reveals that lower distortion energy leads to stability of the transition state corresponding to the S-configuration product. Global reactivity index analysis indicates that the behavior of the NHC catalyst differs significantly before and after the Breslow intermediate debromination. Before debromination, the nucleophilicity of α-bromoenal is enhanced by addition to NHC. However, after debromination, the α,ß-unsaturated acyl azole generates and acts as an electrophilic reagent.

9.
J Org Chem ; 89(5): 3509-3524, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38362658

RESUMO

A photocatalytic annulation cascade of unactivated N-alkene-linked indoles with Langlois' reagent by a radical relay is developed at room temperature under blue LED irradiation. The reaction afforded a series of tri/difluoromethylated pyrrolo[1,2-a]indoles in moderate to good yields. The DFT study suggests that the reaction is ascribed to a rhodamine 6G-induced cyclization cascade involving vinyl addition-radical relay and hydrogen-atom-abstraction (HAA) processes, and interestingly, pyrrolo[1,2-a]indoles are applied as fluorescent dyes into the fluorescence spectrum and live-cell imaging. This paper represents an initial example on photocatalytic cyclization cascades by radical relay and the HAA process.

10.
Fish Shellfish Immunol ; : 109845, 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39159774

RESUMO

High mobility group protein B2 (HMGB2) is an abundant chromatin-associated protein with pivotal roles in transcription, cell proliferation, differentiation, inflammation, and tumorigenesis. However, its immune function in Nile tilapia (Oreochromis niloticus) remains unclear. In this study, we identified a homologue of HMGB2 from Nile tilapia (On-HMGB2) and investigated its functions in the immune response against streptococcus infection. The open reading frame (ORF) of On-HMGB2 spans 642 bp, encoding 213 amino acids, and contains two conserved HMG domains. On-HMGB2 shares over 80% homology with other fish species and 74%-76% homology with mammals. On-HMGB2 was widely distributed in various tissues, with its highest transcript levels in the liver and the lowest in the intestine. Knockdown of On-HMGB2 promoted the inflammatory response in Nile tilapia, increased the bacterial load in the tissues, and led to elevated mortality in Nile tilapia following Streptococcus agalactiae infection. Taken together, On-HMGB2 significantly influences the immune system of Nile tilapia in response to streptococcus infection.

11.
Fish Shellfish Immunol ; 145: 109344, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38151141

RESUMO

Non-specific cytotoxic cells (NCCs) are cytotoxic cell population found in innate immune system of teleost, playing crucial role in immune defense. Non-specific cytotoxic cell receptor protein 1 (NCCRP1) is responsible for recognizing target cells and activating NCCs. That said, since the studies regarding NCCs' role in fish during pathogen infection are few, it is necessary to conduct more comprehensive studies. In this study, we identified NCCRP1 from Trachinotus ovatus (ToNCCRP1). The open reading frame of ToNCCRP1 was found to be 702 bp, encoding a protein of 233 amino acids. Additionally, ToNCCRP1 contained a conserved F-box-associated domain and exhibited more than 61 % similarity to NCCRP1 in other fish species. Quantitative real-time PCR analysis showed that ToNCCRP1 mRNA was generally expressed in all tissues, with the highest level expressed in the liver. Furthermore, the expression of ToNCCRP1 was significantly upregulated following infection with Streptococcus iniae. In vitro experiments demonstrated that recombinant ToNCCRP1 possessed bacterial agglutination and binding capabilities, suggesting its antibacterial function. Additionally, we investigated the immune response of head kidney leukocytes (HKLs) to ToNCCRP1. The challenge experiments revealed that ToNCCRP1 played a role in the immune response by influencing the inflammatory response, regulating signaling pathways and apoptosis in HKLs. These findings suggest that NCCRP1 is involved in the immune defense against pathogenic infections in golden pompano, providing insights into the immune mechanisms of teleost.


Assuntos
Doenças dos Peixes , Proteínas de Peixes , Animais , Proteínas de Peixes/genética , Peixes , Receptores de Superfície Celular , Imunidade Inata/genética
12.
Arch Virol ; 169(4): 81, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38519716

RESUMO

Bacillus subtilis is a Gram-positive bacterium that is widely used in fermentation and in the pharmaceutical industry. Phage contamination occasionally occurs in various fermentation processes and causes significant economic loss. Here, we report the isolation and characterization of a temperate B. subtilis phage, termed phi18-2, from spore powder manufactured in a fermentation plant. Transmission electron microscopy showed that phi18-2 has a symmetrical polyhedral head and a long noncontractile tail. Receptor analysis showed that phi18-2 recognizes wall teichoic acid (WTA) for infection. The phage virions have a linear double-stranded DNA genome of 64,467 bp with identical direct repeat sequences of 309 bp at each end of the genome. In lysogenic cells, the phage genome was found to be present in the cytoplasm without integration into the host cell chromosome, and possibly as a linear phage-plasmid with unmodified ends. Our data may provide some insight into the molecular basis of the unique lysogenic cycle of phage phi18-2.


Assuntos
Fagos Bacilares , Bacteriófagos , Bacteriófagos/genética , Fagos Bacilares/genética , DNA Viral/genética , Lisogenia , Genoma Viral , Plasmídeos/genética , Citoplasma
13.
J Fluoresc ; 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39141272

RESUMO

Ascorbic acid is very important to the metabolic process of the body, but excessive intake can lead to diarrhea, kidney calculi and stomach cramps. However, complicated production procedures and harsh experimental settings limit many detection methods, and a simpler and more accurate measurement method is needed. In this study, a smartphone-assisted ratiometric fluorescence sensor was developed for the portable analysis of ascorbic acid. Leveraging the catalytic properties of MIL-53(Fe) to expedite the conversion of H2O2 into hydroxyl radicals, thereby facilitating the oxidation of o-phenylenediamine and terephthalic acid bridging ligand. The sensor showcased exceptional sensitivity in detecting ascorbic acid within a linear range of 0.3-100 µM, boasting an impressive limit of detection at 0.15 µM. Furthermore, through the utilization of color extraction RGB values captured by smartphones, accurate detection of ascorbic acid was achieved with a detection limit of 0.4 µM. Real fruit samples exhibited robust spiked recovery rates ranging from 91 to 119%, accompanied by relative standard deviations ≤ 4.7%. The MIL-53(Fe) nanozyme-based smartphone-assisted ratiometric fluorescence sensor offers an ascorbic acid fluorescence detection device that is visible, accurate, sensitive, and reasonably priced.

14.
J Phys Chem A ; 128(22): 4483-4492, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38785354

RESUMO

To elucidate the mechanism and origins of chemo- and enantioselectivities of the reaction between aliphatic aldehydes and hydrazones catalyzed by triazolium-derived NHC, density functional theory computations have been performed. According to our calculated results, the whole catalytic cycle for the formation of dihydropyridazinones proceeds via the initial nucleophilic addition of NHC to an aliphatic aldehyde, followed by the concerted intramolecular proton transfer and C-Cl bond cleavage. Subsequent deprotonation generates an enolate intermediate. The enolate intermediate then undergoes 1,4-addition to hydrazone to construct a new carbon-carbon bond. The following ring-closure would lead to a six-membered ring intermediate, which, upon the release of NHC, affords the final product dihydropyridazinone. The computation results reveal that intramolecular proton transfer is significantly promoted by the Brønsted acid DIPEA·H+. The carbon-carbon bond formation step could determine not only the chemoselectivity but also the stereoselectivity and lead to the S-isomer product. It was found that the stereoselectivity arises from a combination of weak interactions, including C-H···O, C-H···N, C-H···π, and LP···π. NHC could enhance the nucleophilicity of the aliphatic aldehyde and facilitate further reaction with hydrazone. This work could be beneficial for the development of new catalytic strategies in the future.

15.
BMC Cardiovasc Disord ; 24(1): 231, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38679696

RESUMO

BACKGROUND: Oxidized low-density lipoprotein (ox-LDL) can initiate and affect almost all atherosclerotic events including endothelial dysfunction. In this text, the role and underlying molecular basis of procyanidin B2 (PCB2) with potential anti-oxidant and anti-inflammatory activities in ox-LDL-induced HUVEC injury were examined. METHODS: HUVECs were treated with ox-LDL in the presence or absence of PCB2. Cell viability and apoptotic rate were examined by CCK-8 assay and flow cytometry, respectively. The mRNA and protein levels of genes were tested by RT-qPCR and western blot assays, respectively. Potential downstream targets and pathways of apple procyanidin oligomers were examined by bioinformatics analysis for the GSE9647 dataset. The effect of PCB2 on THP-1 cell migration was examined by recruitment assay. The effect of PCB2 on oxidative stress was assessed by reactive oxygen species (ROS) level, malondialdehyde (MDA) content, and mitochondrial membrane potential (MMP). RESULTS: ox-LDL reduced cell viability, induced cell apoptosis, and facilitated the expression of oxidized low-density lipoprotein receptor 1 (LOX-1), C-C motif chemokine ligand 2 (MCP-1), vascular cell adhesion protein 1 (VCAM-1) in HUVECs. PCB2 alleviated ox-LDL-induced cell injury in HUVECs. Apple procyanidin oligomers triggered the differential expression of 592 genes in HUVECs (|log2fold-change| > 0.58 and adjusted p-value < 0.05). These dysregulated genes might be implicated in apoptosis, endothelial cell proliferation, inflammation, and monocyte chemotaxis. PCB2 inhibited C-X-C motif chemokine ligand 1/8 (CXCL1/8) expression and THP-1 cell recruitment in ox-LDL-stimulated HUVECs. PCB2 inhibited ox-LDL-induced oxidative stress and nuclear factor kappa-B (NF-κB) activation in HUVECs. CONCLUSION: PCB2 weakened ox-LDL-induced cell injury, inflammation, monocyte recruitment, and oxidative stress by inhibiting the NF-κB pathway in HUVECs.


Assuntos
Anti-Inflamatórios , Apoptose , Biflavonoides , Catequina , Células Endoteliais da Veia Umbilical Humana , Lipoproteínas LDL , NF-kappa B , Estresse Oxidativo , Proantocianidinas , Transdução de Sinais , Humanos , Lipoproteínas LDL/toxicidade , Catequina/farmacologia , Proantocianidinas/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Biflavonoides/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/patologia , Transdução de Sinais/efeitos dos fármacos , NF-kappa B/metabolismo , Apoptose/efeitos dos fármacos , Anti-Inflamatórios/farmacologia , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Monócitos/patologia , Antioxidantes/farmacologia , Células THP-1 , Quimiotaxia de Leucócito/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Receptores Depuradores Classe E/metabolismo , Receptores Depuradores Classe E/genética
16.
Environ Res ; 251(Pt 1): 118545, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38431067

RESUMO

An extensive volume of acid mine drainage (AMD) generated throughout the mining process has been widely regarded as one of the most catastrophic environmental problems. Surface water and groundwater impacted by pollution exhibit extreme low pH values and elevated sulfate and metal/metalloid concentrations, posing a serious threat to the production efficiency of enterprises, domestic water safety, and the ecological health of the basin. Over the recent years, a plethora of techniques has been developed to address the issue of AMD, encompassing nanofiltration membranes, lime neutralization, and carrier-microencapsulation. Nonetheless, these approaches often come with substantial financial implications and exhibit restricted long-term sustainability. Among the array of choices, the permeable reactive barrier (PRB) system emerges as a noteworthy passive remediation method for AMD. Distinguished by its modest construction expenses and enduring stability, this approach proves particularly well-suited for addressing the environmental challenges posed by abandoned mines. This study undertook a comprehensive evaluation of the PRB systems utilized in the remediation of AMD. Furthermore, it introduced the concept of low permeability barrier, derived from the realm of site-contaminated groundwater management. The strategies pertaining to the selection of materials, the physicochemical aspects influencing long-term efficacy, the intricacies of design and construction, as well as the challenges and prospects inherent in barrier technology, are elaborated upon in this discourse.


Assuntos
Mineração , Poluentes Químicos da Água/análise , Recuperação e Remediação Ambiental/métodos , Ácidos , Água Subterrânea/química , Filtração/métodos , Concentração de Íons de Hidrogênio
17.
Environ Res ; 251(Pt 2): 118730, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38492837

RESUMO

The Budyko framework, widely used to quantify the watershed hydrological response to the watershed characteristics and climate variabilities, is continuously refined to overcome the disadvantages of steady state assumption. However, dynamic variations in vegetations and climate variables are not fully integrated including coverages and precipitation regimes of intensity, frequency, and duration. To address this, we developed an innovative approach for determining the parameter ω in the Budyko framework to quantify the hydrological effects of vegetation restoration in a mesoscale watershed located in northern China. We found that fractional vegetation coverage (FVC), heavy precipitation amount (95pTOT), and the number of precipitation days (R01mm) are significant variables for estimating ω to improve the predictive capability of the watershed response. This extended time-varying Budyko framework can rigorously capture the temporal variations and underlying mechanisms of interactions between vegetation dynamic and precipitation regime partitioning precipitation (P) to R. Under the Budyko-Fu framework, compared to constant ω (ω‾) or ω that only considers FVC (ωP) or precipitation regimes (ωFVC) for simulating R, using ω that integrated FVC and precipitation regimes (ωP-FVC) can improve Nash-Sutcliffe efficiency coefficient (NSE) by 24.81%, while reduced the root mean squared error (RMSE) and relative error (RE) by 64.08% and 65.77%, respectively. Although the increase in climatic dryness (PET/P) resulted in decreased R, the increase in FVC has also a significant contribution to this decrease due to vegetation restoration. We highlight that decrease precipitation intensity (95pTOT) and frequency (R01mm) amplified the hydrological effects of vegetation restoration, causing a 79.09∼100.31% increase in R compared to the independent impact of changes in FVC. We conclude that the extended time-varying Budyko framework by precipitation regime is more rigorous for quantifying the hydrological effects of ecological restoration under climate change and providing more reliable approach for adaptive watershed management.


Assuntos
Hidrologia , China , Clima , Chuva , Mudança Climática , Modelos Teóricos , Conservação dos Recursos Naturais/métodos
18.
Int J Hyperthermia ; 41(1): 2382162, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39043380

RESUMO

Background: Central nervous system (CNS) injury is the most prominent feature of heatstroke and the hippocampus is prone to damage. However, the mechanisms underlying the heatstroke-induced hippocampal injury remain unclear. Hyperbaric oxygen (HBO) therapy prevents CNS injury in heatstroke mice. However, the underlying mechanisms of HBO in heatstroke-induced hippocampal injury remain unclear. This study aimed to elucidate the protective effects of HBO against hippocampal injury and its potential role in microglial pyroptosis in heatstroke rats.Methods: A rat heatstroke model and a heat stress model with a mouse microglial cell line (BV2) were, respectively, used to illustrate the effect of HBO on heat-induced microglial pyroptosis in vivo and in vitro. We used a combination of molecular and histological methods to assess microglial pyroptosis and neuroinflammation both in vivo and in vitro.Results: The results revealed that HBO improved heatstroke-induced survival outcomes, hippocampal injury, and neurological dysfunction in rats. In addition, HBO mitigates microglial pyroptosis and reduces the expression of pro-inflammatory cytokines in the hippocampus of heatstroke rats. In vitro experiments showed that HBO attenuated BV2 cell injury under heat stress. Furthermore, HBO prevented heat-induced pyroptosis of BV2 cells, and the expression of pro-inflammatory cytokines IL-18 and IL-1ß was reduced. Mechanistically, HBO alleviates heatstroke-induced neuroinflammation and hippocampal injury by preventing microglial pyroptosis. Conclusions: In conclusion, HBO attenuates heatstroke-induced neuroinflammation and hippocampal injury by inhibiting microglial pyroptosis.


Assuntos
Golpe de Calor , Hipocampo , Oxigenoterapia Hiperbárica , Microglia , Piroptose , Animais , Golpe de Calor/terapia , Golpe de Calor/complicações , Oxigenoterapia Hiperbárica/métodos , Hipocampo/metabolismo , Ratos , Microglia/metabolismo , Masculino , Ratos Sprague-Dawley , Camundongos
19.
BMC Vet Res ; 20(1): 100, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38468314

RESUMO

BACKGROUND: Salmonella enteritidis (SE) is a major zoonotic pathogen and causes infections in a variety of hosts. The development of novel vaccines for SE is necessary to eradicate this pathogen. Genetically engineered attenuated live vaccines are more immunogenic and safer. Thus, to develop a live attenuated Salmonella vaccine, we constructed a cheV gene deletion strain of SE (named ΔcheV) and investigated the role of cheV in the virulence of SE. First, the ability to resist environmental stress in vitro, biofilm formation capacity, drug resistance and motility of ΔcheV were analyzed. Secondly, the bacterial adhesion, invasion, intracellular survival assays were performed by cell model. Using a mouse infection model, an in vivo virulence assessment was conducted. To further evaluate the mechanisms implicated by the reduced virulence, qPCR analysis was utilized to examine the expression of the strain's major virulence genes. Finally, the immune protection rate of ΔcheV was evaluated using a mouse model. RESULTS: Compared to C50336, the ΔcheV had significantly reduced survival ability under acidic, alkaline and thermal stress conditions, but there was no significant difference in survival under oxidative stress conditions. There was also no significant change in biofilm formation ability, drug resistance and motility. It was found that the adhesion ability of ΔcheV to Caco-2 cells remained unchanged, but the invasion ability and survival rate in RAW264.7 cells were significantly reduced. The challenge assay results showed that the LD50 values of C50336 and ΔcheV were 6.3 × 105 CFU and 1.25 × 107 CFU, respectively. After the deletion of the cheV gene, the expression levels of fimD, flgG, csgA, csgD, hflK, lrp, sipA, sipB, pipB, invH, mgtC, sodC, rfbH, xthA and mrr1 genes were significantly reduced. The live attenuated ΔcheV provided 100% protection in mice against SE infection. CONCLUSION: All the results confirmed that the deletion of the cheV gene reduces the virulence of SE and provides significant immune protection in mice, indicating that ΔcheV could be potential candidates to be explored as live-attenuated vaccines.


Assuntos
Salmonelose Animal , Vacinas contra Salmonella , Animais , Humanos , Salmonella enteritidis , Vacinas contra Salmonella/genética , Virulência/genética , Proteínas de Bactérias , Células CACO-2 , Salmonelose Animal/microbiologia
20.
Clin Lab ; 70(5)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38747911

RESUMO

BACKGROUND: This study aims to evaluate the ability of laboratories to perform spinal muscular atrophy (SMA) genetic testing in newborns based on dried blood spot (DBS) samples, and to provide reference data and advance preparation for establishing the pilot external quality assessment (EQA) scheme for SMA genetic testing of newborns in China. METHODS: The pilot EQA scheme contents and evaluation principles of this project were designed by National Center for Clinical Laboratories (NCCL), National Health Commission. Two surveys were carried out in 2022, and 5 batches of blood spots were submitted to the participating laboratory each time. All participating laboratories conducted testing upon receiving samples, and test results were submitted to NCCL within the specified date. RESULTS: The return rates were 75.0% (21/28) and 95.2% (20/21) in the first and second surveys, respectively. The total return rate of the two examinations was 83.7% (41/49). Nineteen laboratories (19/21, 90.5%) had a full score passing on the first survey, while in the second survey twenty laboratories (20/20, 100%) scored full. CONCLUSIONS: This pilot EQA survey provides a preliminary understanding of the capability of SMA genetic testing for newborns across laboratories in China. A few laboratories had technical or operational problems in testing. It is, therefore, of importance to strengthen laboratory management and to improve testing capacity for the establishment of a national EQA scheme for newborn SMA genetic testing.


Assuntos
Testes Genéticos , Atrofia Muscular Espinal , Triagem Neonatal , Humanos , Recém-Nascido , Atrofia Muscular Espinal/diagnóstico , Atrofia Muscular Espinal/genética , Projetos Piloto , Testes Genéticos/normas , Testes Genéticos/métodos , Triagem Neonatal/normas , Triagem Neonatal/métodos , China , Teste em Amostras de Sangue Seco/normas , Teste em Amostras de Sangue Seco/métodos , Garantia da Qualidade dos Cuidados de Saúde , Laboratórios Clínicos/normas , Proteína 1 de Sobrevivência do Neurônio Motor/genética
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